Stairway.



UNTTnn STATns PATENT umori.

JOSEPH PICCARD, OF BOSTON, MASSACHUSETTS.

STAi RWY.

SPECIFICATION forming part of Letters Patent No. '71 0,886, dated October '7, 1902.

Application filed August 1,1902y T0 a/ZZ 'Ll/hom, t mty/ concern:

Beit known that I, JOSEPH PrcoARDr, a citizen ofthe United States, and a resident of Boston, in the county of Suffolk, State of Massachusetts, have invented certain new and useful Improvements in Stairways, of which the following is a full, clear, and exact description.

Myinven tion relates to stairways of the [ireproof variety, which'are so made by being wholly or partially built up from concrete; and the essential feature of my invention is the metal frame by means ofwhich the concrete stairs are supported andat the same time protected against injury from wear and which performs the added function of a templet for enabling the stairs to be accurately and readily formed.

Referring to the drawings forming part of this speciiication, Figure l is a perspective view of a part of my stairway-frame. Fig. 2 is a perspective View, on a smaller scale, of the lower part of said'frame. Fig. 3 is aside sectional view of a part of the stairway, showing the manner of its formation. Fig. 4 is a. plan view of one of the elements of the frame.

The supporting part of my frame consists of the angle-irons 3 and the central T-beam lO, bound together by the cross-bars 6, 7, and ll, said T-beam being parallel with but midway between the other two beams. Parallel with the upright webs of the angle-irons 3 and a short distance away therefrom are the bars 4, to which bars and webs are bolted or riveted the end sections 2 of the straps l, said ends or arms 2 being bent at right angles to the body of each strap. Said bodies and arms are arranged to lie horizontally when the frame is in its place and are so proportioned that the upper edges of each are about seven and one-half inches above the similar edges of the strap next below or whatever other dimension may be determined on for the riser of the stairway. Furth er, the horizontal dis- Canoes between the front edges of the bodies l are made about nine inches or whatever other size of tread may be desired. The foot of this frame I prefer to form of the cross strips or bars 6 and 7 and the sides 5, the parts 5 and 6 being preferably in one length of iron about one inch in vertical dimension, the object of such dimension being to corre- Scrial No. 117,970. (No model.)

spond with the usual thickness ofthe marble blocks or slabs used upon the iioor. For the same reason l prefer to have the strap-iron forming the bodies and arms l 2 about au inch wide, while the thickness is preferably about a quarter of an inch. Said parts l 2 for the purpose of more clearly designating them by the principal function which they perform I hereinafter term edging-strips.

As a general thing` I prefer to construct the frame for my stairway before applying the same to the place for which it is intended, because of the greater facility for accuracy and'economy in production which the shop affords. In many cases, however, itis better to have the parts simply cutout and punched to measure and bolt or rivet them together where they are to be erected, especially for the larger and bulkier stairways.

NVhichever way is found most expedient, the stairwaysframe having been put in position the next step is to till the same with concrete or other material of the character. This is done by first temporarily securing planking 16, Fig. 3, up against the under surfaces of the beams 3 and lO, filling the space between the same. Then beginning at the lowest step the frame is filled in with the concrete or other material, both the tread of each step and the riser thereof being trued up by the edging-strips. The front face or riser of each step is preferably formed by a suitable board or plank held against the front face of the edging-strip and supported upon the upper edge of the arms below. For this purpose the bars 4 are very convenient, since a couple of sticks braced against such board and the corners where said bars cross the arms 2 will effectually hold said board against the pressure of the concrete in the step above. By suitably supporting a straightedged scraper upon the arms and body of the edgingstrip the tread of each stepmay be with equal accuracy and ease made perfectly true and level. lf desired, thin tiles or slabs may be applied to the steps, those for the risers being putin place before the concrete is introduced, but those for the treads after. After the cement has sufliciently hardened the planking and other temporary appliances are removed and the under surface of the stairs properly skinn IOO coated or simply whitewashed. As is evident, the edging-strips l being of comparatively heavyiron effectually protect'the edges of the stairs from being worn or broken in use. Even heavy packing-cases dropping against the corners will not fracture the concrete beneath and behind the iron edgingstrips. The stairs which I have in this manner constructed I have found to remain in perfect repair even after constant and heavy use.

As Will be seen by reference to Fig. 3,when the frame is filled in with concrete the bars 4 form trusses with the angle-irons 3 and so materially strengthen the stairway above what the angle-irons alone can do. For comparatively narrow stairs the frame is sufficiently strong Without the central T-beam 10; but for those of considerable width or which are to sustain heavy usage it is necessary to employ said T-beam.

What I claim as my invention, and for which I desire Letters Patent, is as follows, to wit:

1. In a stairway, the frame comprising the angle-irons and the edging-strips secured thereto, each edging-strip consisting of the body and arms bent at right angles to each other, substantially as described.

2. In a stairway, the combination with suitable supporting-beams of the edgingstrips fixed thereto at an oblique angle and all parallel with one another, each edgingstrip consisting of the body and the arms bent at right angles thereto, substantially as described.

3. In a stairway, the combination of the angle-irons, the bars parallel thereto, and the edging-strips fixed to said angle-irons and bars, substantially as described.

4. The frame for stairways consisting of the two angle-irons, the bars parallel thereto, the edging-strips fixed to said angle-irons and-bars, the T-beam between said angleirons, and the cross-bars securing the same in place, substantially as described.

5. The combination with the angle-irons and the edging-strips affixed thereto, of the concrete filling the space between said angle-irons and edging-strips, substantially as described.

In testimony that I claim the foregoing invention I have hereunto set my hand this 28th day of July, 1902.

JOSEPH PICCARDI.

Witnesses:

A. B. UPHAM, FRANK S. HAMMOND. 

